/***************************************************************************//* *//* ftcache.h *//* *//* FreeType Cache subsystem (specification). *//* *//* Copyright 1996-2001 by *//* David Turner, Robert Wilhelm, and Werner Lemberg. *//* *//* This file is part of the FreeType project, and may only be used, *//* modified, and distributed under the terms of the FreeType project *//* license, LICENSE.TXT. By continuing to use, modify, or distribute *//* this file you indicate that you have read the license and *//* understand and accept it fully. *//* *//***************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /********* *********/ /********* WARNING, THIS IS BETA CODE. *********/ /********* *********/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ #ifndef __FTCACHE_H__#define __FTCACHE_H__ #include <ft2build.h>#include FT_GLYPH_H FT_BEGIN_HEADER /*************************************************************************/ /* */ /* <Section> */ /* cache_subsystem */ /* */ /* <Title> */ /* Cache Sub-System */ /* */ /* <Abstract> */ /* How to cache face, size, and glyph data with FreeType 2. */ /* */ /* <Description> */ /* This section describes the FreeType 2 cache sub-system which is */ /* stile in beta. */ /* */ /* <Order> */ /* FTC_Manager */ /* FTC_FaceID */ /* FTC_Face_Requester */ /* */ /* FTC_Manager_New */ /* FTC_Manager_Lookup_Face */ /* FTC_Manager_Lookup_Size */ /* */ /* FTC_Node */ /* FTC_Node_Ref */ /* FTC_Node_Unref */ /* */ /* FTC_Font */ /* FTC_ImageDesc */ /* FTC_ImageCache */ /* FTC_ImageCache_New */ /* FTC_ImageCache_Lookup */ /* */ /* FTC_SBit */ /* FTC_SBitCache */ /* FTC_SBitCache_New */ /* FTC_SBitCache_Lookup */ /* */ /* */ /* FTC_Image_Desc */ /* FTC_Image_Cache */ /* FTC_Image_Cache_Lookup */ /* */ /* FTC_SBit_Cache */ /* FTC_SBit_Cache_Lookup */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** BASIC TYPE DEFINITIONS *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FTC_FaceID */ /* */ /* <Description> */ /* A generic pointer type that is used to identity face objects. The */ /* contents of such objects is application-dependent. */ /* */ typedef FT_Pointer FTC_FaceID; /*************************************************************************/ /* */ /* <FuncType> */ /* FTC_Face_Requester */ /* */ /* <Description> */ /* A callback function provided by client applications. It is used */ /* to translate a given @FTC_FaceID into a new valid @FT_Face object. */ /* */ /* <Input> */ /* face_id :: The face ID to resolve. */ /* */ /* library :: A handle to a FreeType library object. */ /* */ /* data :: Application-provided request data. */ /* */ /* <Output> */ /* aface :: A new @FT_Face handle. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The face requester should not perform funny things on the returned */ /* face object, like creating a new @FT_Size for it, or setting a */ /* transformation through @FT_Set_Transform! */ /* */ typedef FT_Error (*FTC_Face_Requester)( FTC_FaceID face_id, FT_Library library, FT_Pointer request_data, FT_Face* aface ); /*************************************************************************/ /* */ /* <Struct> */ /* FTC_FontRec */ /* */ /* <Description> */ /* A simple structure used to describe a given `font' to the cache */ /* manager. Note that a `font' is the combination of a given face */ /* with a given character size. */ /* */ /* <Fields> */ /* face_id :: The ID of the face to use. */ /* */ /* pix_width :: The character width in integer pixels. */ /* */ /* pix_height :: The character height in integer pixels. */ /* */ typedef struct FTC_FontRec_ { FTC_FaceID face_id; FT_UShort pix_width; FT_UShort pix_height; } FTC_FontRec; /* */ #define FTC_FONT_COMPARE( f1, f2 ) \ ( (f1)->face_id == (f2)->face_id && \ (f1)->pix_width == (f2)->pix_width && \ (f1)->pix_height == (f2)->pix_height ) #define FT_POINTER_TO_ULONG( p ) ((FT_ULong)(FT_Pointer)(p)) #define FTC_FACE_ID_HASH( i ) \ ((FT_UInt32)(( FT_POINTER_TO_ULONG( i ) >> 3 ) ^ \ ( FT_POINTER_TO_ULONG( i ) << 7 ) ) ) #define FTC_FONT_HASH( f ) \ (FT_UInt32)( FTC_FACE_ID_HASH((f)->face_id) ^ \ ((f)->pix_width << 8) ^ \ ((f)->pix_height) ) /*************************************************************************/ /* */ /* <Type> */ /* FTC_Font */ /* */ /* <Description> */ /* A simple handle to an @FTC_FontRec structure. */ /* */ typedef FTC_FontRec* FTC_Font; /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** CACHE MANAGER OBJECT *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FTC_Manager */ /* */ /* <Description> */ /* This object is used to cache one or more @FT_Face objects, along */ /* with corresponding @FT_Size objects. */ /* */ typedef struct FTC_ManagerRec_* FTC_Manager; /*************************************************************************/ /* */ /* <Type> */ /* FTC_Node */ /* */ /* <Description> */ /* An opaque handle to a cache node object. Each cache node is */ /* reference-counted. A node with a count of 0 might be flushed */ /* out of a full cache whenever a lookup request is performed. */ /* */ /* If you lookup nodes, you have the ability to "acquire" them, i.e., */ /* to increment their reference count. This will prevent the node */ /* from being flushed out of the cache until you explicitly "release" */ /* it (see @FTC_Node_Release). */ /* */ /* See also @FTC_BitsetCache_Lookup and @FTC_ImageCache_Lookup. */ /* */ typedef struct FTC_NodeRec_* FTC_Node; /*************************************************************************/ /* */ /* <Function> */ /* FTC_Manager_New */ /* */ /* <Description> */ /* Creates a new cache manager. */ /* */ /* <Input> */ /* library :: The parent FreeType library handle to use. */ /* */ /* max_faces :: Maximum number of faces to keep alive in manager. */ /* Use 0 for defaults. */ /* */ /* max_sizes :: Maximum number of sizes to keep alive in manager. */ /* Use 0 for defaults. */ /* */ /* max_bytes :: Maximum number of bytes to use for cached data. */ /* Use 0 for defaults. */ /* */ /* requester :: An application-provided callback used to translate */ /* face IDs into real @FT_Face objects. */ /* */ /* req_data :: A generic pointer that is passed to the requester */ /* each time it is called (see @FTC_Face_Requester). */ /* */ /* <Output> */ /* amanager :: A handle to a new manager object. 0 in case of */ /* failure. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ FT_EXPORT( FT_Error ) FTC_Manager_New( FT_Library library, FT_UInt max_faces, FT_UInt max_sizes, FT_ULong max_bytes, FTC_Face_Requester requester, FT_Pointer req_data, FTC_Manager *amanager ); /*************************************************************************/ /* */ /* <Function> */ /* FTC_Manager_Reset */ /* */ /* <Description> */ /* Empties a given cache manager. This simply gets rid of all the */ /* currently cached @FT_Face and @FT_Size objects within the manager. */ /* */ /* <InOut> */ /* manager :: A handle to the manager. */ /* */ FT_EXPORT( void ) FTC_Manager_Reset( FTC_Manager manager ); /*************************************************************************/ /* */ /* <Function> */ /* FTC_Manager_Done */ /* */ /* <Description> */ /* Destroys a given manager after emptying it. */ /* */ /* <Input> */ /* manager :: A handle to the target cache manager object. */ /* */ FT_EXPORT( void ) FTC_Manager_Done( FTC_Manager manager ); /*************************************************************************/ /* */ /* <Function> */ /* FTC_Manager_Lookup_Face */ /* */ /* <Description> */ /* Retrieves the @FT_Face object that corresponds to a given face ID */ /* through a cache manager. */ /* */ /* <Input> */ /* manager :: A handle to the cache manager. */ /* */ /* face_id :: The ID of the face object. */ /* */ /* <Output> */ /* aface :: A handle to the face object. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The returned @FT_Face object is always owned by the manager. You */ /* should never try to discard it yourself. */ /* */ /* The @FT_Face object doesn't necessarily have a current size object */ /* (i.e., face->size can be 0). If you need a specific `font size', */ /* use @FTC_Manager_Lookup_Size instead. */ /* */ /* Never change the face's transformation matrix (i.e., never call */ /* the @FT_Set_Transform function) on a returned face! If you need */ /* to transform glyphs, do it yourself after glyph loading. */ /* */ FT_EXPORT( FT_Error ) FTC_Manager_Lookup_Face( FTC_Manager manager, FTC_FaceID face_id, FT_Face *aface ); /*************************************************************************/ /* */ /* <Function> */ /* FTC_Manager_Lookup_Size */ /* */ /* <Description> */ /* Retrieves the @FT_Face and @FT_Size objects that correspond to a */ /* given @FTC_SizeID. */ /* */ /* <Input> */ /* manager :: A handle to the cache manager. */ /* */ /* size_id :: The ID of the `font size' to use. */ /* */ /* <Output> */ /* aface :: A pointer to the handle of the face object. Set it to */ /* zero if you don't need it. */ /* */ /* asize :: A pointer to the handle of the size object. Set it to */ /* zero if you don't need it. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The returned @FT_Face object is always owned by the manager. You */ /* should never try to discard it yourself. */ /* */ /* Never change the face's transformation matrix (i.e., never call */ /* the @FT_Set_Transform function) on a returned face! If you need */ /* to transform glyphs, do it yourself after glyph loading. */ /* */ /* Similarly, the returned @FT_Size object is always owned by the */ /* manager. You should never try to discard it, and never change its */ /* settings with @FT_Set_Pixel_Sizes or @FT_Set_Char_Size! */ /* */ /* The returned size object is the face's current size, which means */ /* that you can call @FT_Load_Glyph with the face if you need to. */ /* */ FT_EXPORT( FT_Error ) FTC_Manager_Lookup_Size( FTC_Manager manager, FTC_Font font, FT_Face *aface, FT_Size *asize ); FT_END_HEADER #endif /* __FTCACHE_H__ */ /* END */